1.  If 20% of a = b, then b% of 20 is the same as:
A. 4% of a
B. 5% of a
C. 20% of a
D. None of these

Answer: Option A

Explanation:

20% of a = b      20 a = b.
100

b% of 20

= b x 20 = 20 a x 1 x 20 = 4 a
100 100 100 100

= 4% of a.